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Apicomplexan parasites cause persistent mortality and morbidity worldwide through diseases including malaria, toxoplasmosis, and cryptosporidiosis. Ca2+ signaling pathways have been repurposed in these eukaryotic pathogens to regulate parasite-specific cellular processes governing the replicative and lytic phases of the infectious cycle, as well as the transition between them. Despite the presence of conserved Ca2+-responsive proteins, little is known about how specific signaling elements interact to impact pathogenesis. We mapped the Ca2+-responsive proteome of the model apicomplexan Taxoplasma gondii via time-resolved phosphoproteomics and thermal proteome profiling. The waves of phosphoregulation following PKG activation and stimulated Ca 2+ release corroborate known physiological changes but identify specific proteins operating in these pathways. Thermal profiling of parasite extracts identified many expected Ca2+-responsive proteins, such as parasite Ca2+-dependent protein kinases. Our approach also identified numerous Ca2+- responsive proteins that are not predicted to bind Ca2+, yet are critical components of the parasite signaling network. We characterized protein phosphatase 1 (PP1) as a Ca2+-responsive enzyme that relocalized to the parasite apex upon Ca2+ store release. Conditional depletion of PP1 revealed that the phosphatase regulates Ca2+ uptake to promote parasite motility. PP1 may thus be partly responsible for Ca2+-regulated serine/threonine phosphatase activity in apicomplexan parasites. [ABSTRACT FROM AUTHOR]

B 10 O cluster adopts an interesting umbrella structure with a transition-metal-like central boron atom, which is demonstrated by the complexation with an arene-analog (B 8) and a carbonyl-analog (BO). [Display omitted] • The B 10 O cluster adopts a fascinating umbrella architecture with a structural configuration of B 8 -B-BO. • The upper B 8 -B motif possesses 6σ + 6π double aromaticity. • The central boron atom exhibits interesting transition-metal-like bonding property. We report a new candidate B 10 O with the transition-metal-like boron atom in the boron monoxide clusters family. It adopts an umbrella architecture with a structural configuration of B 8 -B-BO. Significantly, the central boron atom is coordinated with both arene analog (B 8) and carbonyl analog (BO), demonstrating its transition-metal property. Chemical bonding analyses suggest that the upper B 9 (B 8 -B) possesses the double (6σ + 6π) aromaticity, which gives rise to the extraordinary stability of B 10 O molecular umbrella. As a dynamically stabilized global minimum, the neutral B 10 O molecular umbrella is promising to be synthesized in the condensed phase. [ABSTRACT FROM AUTHOR]

The objective was to find the role of long-non-coding RNA zinc finger antisense 1 (lncRNA ZFAS1)/microRNA (miR)-129/high-mobility group box protein 1 (HMGB1) axis in polycystic ovary syndrome (PCOS). Ovarian granulosa cells from non-PCOS patients and PCOS patients were collected, and HMGB1, miR-129 and lncRNA ZFAS1 expression were detected. Ovarian granulosa cells were transfected with si-ZFAS1 or miR-129 mimics to verify their roles in P4 and E2 secretion, and the biological functions of ovarian granulosa cells. LncRNA ZFAS1 and HMGB1 were elevated, while miR-129 was down-regulated in ovarian granulosa cells of PCOS patients. Down-regulated lncRNA ZFAS1 or overexpressed miR-129 could decrease HMGB1 expression, increase P4 and E2 secretion, promote proliferation activity while inhibit apoptosis of ovarian granulosa cells in PCOS. LncRNA ZFAS1 could bind to miR-129 to promote HMGB1 expression, thereby affecting the endocrine disturbance, proliferation and apoptosis of ovarian granulosa cells in PCOS. • A novel report on the role of ZFAS1/miR-129//HMGB1 in PCOS. • Increased ZFAS1, HMGB1 and decreased miR-129 are found in PCOS. • ZFAS1 acts as a ceRNA of miR-129 in ovarian granulosa cells of PCOS. • HMGB1 is the direct target gene of miR-129. • Increased miR-129 and decreased ZFAS1 promote growth of ovarian granulosa cells. [ABSTRACT FROM AUTHOR]

This study presents calcium isotope data for co-existing clinopyroxenes (cpx), orthopyroxenes (opx), and olivine (ol) in mantle xenoliths to investigate Ca isotopic fractionation in the upper mantle. δ 44/40 Ca (δ 44/40 Ca (‰) = ( 44 Ca/ 40 Ca) SAMPLE /( 44 Ca/ 40 Ca) SRM915a − 1) in opx varies from 0.95 ± 0.05‰ to 1.82 ± 0.01‰ and cpx from 0.71 ± 0.06‰ to 1.03 ± 0.12‰ (2se). δ 44/40 Ca in ol (P-15) is 1.16 ± 0.08‰, identical to δ 44/40 Ca of the co-existing opx (1.12 ± 0.09‰, 2se). The Δ 44/40 Ca opx−cpx (Δ 44/40 Ca opx−cpx = δ 44/40 Ca opx –δ 44/40 Ca cpx ) shows a large variation ranging from −0.01‰ to 1.11‰ and it dramatically increases with decreasing of Ca/Mg (atomic ratio) in opx. These observations may reflect the effect of opx composition on the inter-mineral equilibrium fractionation of Ca isotopes, consistent with the theoretical prediction by first-principles theory calculations (Feng et al., 2014). Furthermore, Δ 44/40 Ca opx−cpx decreases when temperature slightly increases from 1196 to 1267 K. However, the magnitude of such inter-mineral isotopic fractionation (1.12‰) is not consistent with the value calculated by the well-known correlation between inter-mineral isotope fractionation factors and 1/ T 2 (Urey, 1947). Instead, it may reflect the temperature control on crystal chemistry of opx (i.e., Ca content), which further affects Δ 44/40 Ca opx−cpx . The calculated δ 44/40 Ca of bulk peridotites and pyroxenites range from 0.76 ± 0.06‰ to 1.04 ± 0.12‰ (2se). Notably, δ 44/40 Ca of bulk peridotites are positively correlated with CaO and negatively with MgO content. Such correlations can be explained by mixing between a fertile mantle end-member and a depleted one with low δ 44/40 Ca, indicating that Ca isotopes could be a useful tool in studying mantle evolution. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii possesses a bifunctional farnesyl diphosphate (FPP)/geranylgeranyl diphosphate (GGPP) synthase (TgFPPS) that synthesizes C15 and C20 isoprenoid diphosphates from isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP). This enzyme has a unique arrangement of the fourth and fifth amino acid upstream from the first aspartic rich motif (FARM) where the fourth amino acid is aromatic and the fifth is a cysteine. We mutated these amino acids, converting the enzyme to an absolute FPPS by changing the cysteine to a tyrosine. The enzyme could be converted to an absolute GGPPS by changing both the fourth and fifth amino acids to alanines. We also constructed four mutated TgFPPSs whose regions around the first aspartate rich motif were replaced with the corresponding regions of FPP synthases from Arabidopsis thaliana or Saccharomyces cerevisiae or with the corresponding regions of GGPP synthases from Homo sapiens or S. cerevisiae. We determined that the presence of a cysteine at the fifth position is essential for the TgFPPS bifunctionality. We also found that the length of the N-terminal domain plays a role in determining the specificity and the length of the isoprenoid product. Phylogenetic analysis supports the grouping of this enzyme with other type I FPPSs, but the biochemical data indicate that TgFPPS has unique characteristics that differentiate it from mammalian FPPSs and GGPPSs and is therefore an important drug target. [ABSTRACT FROM AUTHOR]

Trypanosoma cruzi, the agent of Chagas disease, does not seem to control gene expression through regulation of transcription initiation and makes use of post-transcriptional mechanisms. We report here a 43-nt U-rich RNA element located in the 3'-untranslated region (3'-UTR) of a large number of T. cruzi mRNAs that is important for mRNA abundance in the intracellular amastigote stage of the parasite. Whole genome scan analysis, differential display RT-PCR, Northern blot, and RT-PCR analyses were used to determine the transcript levels of more than 900 U-rich-containing mRNAs of large gene families as well as single and low copy number genes. Our results indicate that the 43-nt U-richmRNAelement is preferentially present in amastigotes. The cis-element of a protein kinase 3'-UTR but not its mutated version promoted the expression of the green fluorescent protein reporter gene in amastigotes. The regulatory ciselement, but not its mutated version, was also shown to interact with the trypanosome-specific RNA-binding protein (RBP) TcUBP1 but not with other related RBPs. Co-immunoprecipitation experiments of TcUBP1-containing ribonucleoprotein complexes formed in vivo validated the interaction with representative endogenous RNAs having the element. These results suggest that this 43-nt U-rich element together with other yet unidentified sequences might be involved in the modulation of abundance and/or translation of subsets of transcripts in the amastigote stage. [ABSTRACT FROM AUTHOR]

Farnesyl-diphosphate synthase (FPPS) catalyzes the synthesis of farnesyl diphosphate, an important precursor of sterols, dolichols, ubiquinones, and prenylated proteins. We report the cloning and characterization of two Toxoplasma gondii famesyl-diphosphate synthase (TgFPPS) homologs. A single genetic locus produces two transcripts, TgFPPS and TgFPPSi, by alternative splicing. Both isoforms were heterologously expressed in Escherichia coli, but only TgFPPS was active. The protein products predicted from the nucleotide sequences have 646 and 605 amino acids and apparent molecular masses of 69.5 and 64.5 kDa, respectively. Several conserved sequence motifs found in other prenyl-diphosphate synthases are present in both TgFPPSs. TgFPPS was also expressed in the baculovirus system and was biochemically characterized. In contrast to the FPPS of other eukaryotic organisms, TgFPPS is bifunetional, catalyzing the formation of both farnesyl diphosphate and geranylgeranyl diphosphate. TgFPPS localizes to the mitochondria, as determined by the co-localisation of the affinity-purified antibodies against the protein with MitoTracker, and in accord with the presence of an N-terminal mitochondria-targeting signal in the protein. This enzyme is an attractive target for drug development, because the order of inhibition of the enzyme by a number of bisphosphonates is the same as that for inhibition of parasite growth. In summary, we report the first bifunctional farnesyl-diphosphate/geranylgeranyldiphosphate synthase identified in eukaryotes, which, together with previous results, establishes this enzyme as a valid target for the chemotherapy of toxoplasmosis. [ABSTRACT FROM AUTHOR]

To investigate the effects of melt metasomatism on Ca isotope fractionation in the upper mantle, we report data for xenoliths of mantle rocks including composite peridotites (lherzolites and coexisting pyroxenite veins), wehrlites as well as eclogites and their minerals. The δ44/40Ca in clinopyroxenes (cpx) are ~0.3‰ lower than in coexisting garnets in eclogites from the Udachnaya kimberlite in the central Siberian craton, likely due to equilibrium isotope fractionation controlled by mineral structure. The δ44/40Ca in the pyroxenite veins (cumulates from mafic melts) and their host peridotites from Tariat in Mongolia range from 0.88‰ to 1.05‰ and are close to the Bulk Silicate Earth (BSE) value (0.95 ± 0.05‰). Calcium-Fe-rich low-orthopyroxene lherzolites and wehrlites (LW series) from Tok in the SE Siberian craton were formed by reaction of lherzolites and harzburgites with percolating silica-undersaturated melts. The δ44/40Ca (0.65‰–0.87‰) in the Tok peridotites are negatively correlated with Ca/Al, (Gd/Yb) N and positively with Mg# (indices of melt-rock reaction degrees). The δ44/40Ca ratios in the LW series rocks are lighter than the BSE estimate, and similar to δ44/40Ca in their host basalt and an olivine-cpx cumulate (0.70‰–0.76‰). These observations on the Tok suite can be explained by reaction of refractory peridotite protoliths with melts derived from mixed eclogite and peridotite sources. Overall, the δ44/40Ca variations in eclogites, wehrlites, and various rocks related to silicate melts in the mantle, demonstrate that melt metasomatism plays an important role in producing mantle Ca isotope heterogeneity. The data for coexisting garnet and cpx in eclogites outline a potential for garnet to affect Ca isotope inter-mineral and solid-melt fractionation in the mantle. [ABSTRACT FROM AUTHOR]

Background. The formulation of Bu Shen Yang Xue (BSYX) has been clinically used in treating gynecologic disease in China, especially for the development of the endometrium. Endometrial carcinoma is the most common malignant tumor of the female genital tract in developed countries. And few studies have been reported on the antitumor activity of BSYX. Therefore, this study aimed to investigate the effect of BSYX on endometrial cancer and make an initial discussion of the underlining mechanisms in Ishikawa cells. Methods and Results. Firstly, 60 SPF female nude mice were randomly divided into control group, model group, BSYX group, and positive group. The models of subcutaneous tumor xenograft of nude mice were established by injection of human endometrial carcinoma cell line Ishikawa tumor cell suspension. Compared with model group, BSYX reduced effectively tumor volume and changed pathological feature in mice tumor issue. Meanwhile, proteins from tumor issues were detected by western blot analysis. The protein levels of follicle-stimulating hormone receptor (FSHR), p-Akt/Akt, Gankyrin, and cyclinD1 in the model group were higher than those in control group but the expression in BSYX group was lower than that in the model group. The hypoxia inducible factor alpha (HIF-α) protein level in the model group was lower than those in control group and upregulated in BSYX group. In addition, Ishikawa cells were cultured and then exposed to follicle-stimulating hormone (FSH), LY294002, a highly selective PI3K inhibitor and serum containing BSYX, respectively. LY294002 and BSYX markedly decreased the cancer cell viability and migration ability and increased the apoptosis rate. FSH promoted the cancer cell ability and migration ability. LY294002 and BSYX evidently downregulated the proteins levels of FSHR, p-Akt/Akt, Gankyrin, and cyclinD1 and upregulated the expression of HIF-α protein, and FSH was on the opposite. Conclusions. Taken together, our results showed that the formulation of BSYX had antitumor effect on endometrial cancer in vivo and in vitro and was related with FSH/PI3K/AKT/Gankyrin/HIF-α/cyclinD1 transduction pathway. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented which discusses the effectivity of autologous cytokine-induced killer (CIK) cells as treatment for patient with orbital diffuse large B-cell lymphoma.

This study reports Ca-Fe isotope compositions of mineral separates in a set of peridotite xenoliths including ten lherzolites, one harzburgite, and one wehrlite from Hainan Island, south China. Iron isotope compositions show a small variation (<0.15‰ of δ56/54Fe) among olivine (ol), orthopyroxene (opx), and clinopyroxene (cpx). Δ44/40Ca opx-cpx (δ44/40Ca opx -δ44/40Ca cpx) show a large range from 0.00‰ to 1.23‰. Together with data in previous studies, Δ44/40Ca opx-cpx in mantle xenoliths worldwide show a negative correlation with the apparent temperatures, which cannot be explained by equilibrium fractionation. Instead, the observed inter-mineral Ca isotope fractionation between opx and cpx (>2‰) in previous studies should be dominated by disequilibrium sub-solidus Ca redistribution between cpx and opx, which is driven by the changes of mantle temperature and chemical composition in pyroxene. The wehrlite, which was formed by reaction of peridotite with an evolved, silica-undersaturated melt, has δ44/40Ca of 3.22‰ and δ56/54Fe of 0.22‰, significantly heavier than the value of fertile mantle. Such heavy isotope signatures in the wehrlite are best explained by diffusion during the metasomatic melt percolating the refractory mantle. In summary, this study reveals that significant kinetic Ca isotope fractionations could occur in the mantle by inter-mineral Ca diffusion during re-equilibration upon cooling and Ca diffusion from melt into peridotite during melt percolation. [ABSTRACT FROM AUTHOR]

Both Pacific and Neo-Tethys plates had major influences on the Cretaceous magmatisms in southeastern China. The subduction of the Neo-Tethys plate is, however, not well studied. This paper reports zircon U-Pb ages, Lu-Hf isotopes, whole-rock geochemistry, and Sr-Nd isotopes for the Qianjia intrusive rocks in Hainan Island, southeast China. LA-inductively coupled plasma mass spectrometry zircon U-Pb dating of granites and dark enclave monzonite in the area yield magmatic crystallization ages of ca. 100 Ma, which are consistent with other Late Cretaceous granites, e.g. Baocheng, Tunchang, and Yaliang. Both rocks show high-K calc-alkaline compositions and metaluminous to weakly peraluminous signatures belonging to I-type rocks. They are enriched in the alkalis, Rb, Th, U, K, and light rare earth elements, depleted in Nb, Ta, Ti, and P, and characterized by high Al2O3 contents (14-15 wt%) and high Mg# values (50-53). Among them, some of granodiorites have geochemical affinities of adakitic rocks. Zircon εHf(t) values range from −5.97 to −1.18, with fairly constant whole-rock Sr-Nd isotopes (ISr = 0.7084-0.7086; εNd(t) = −4.97 to −4.29) similar with those of the Cretaceous mafic dikes (136-81 Ma) in Hainan Island, which are the result of partial melting of subduction-related sub-continental lithospheric mantle. Combined with Sr-Nd isotopes and negative Hf isotope, Qianjia intrusive rocks were likely derived from hybrid melts of underplated continental crust-derived with mantle-derived, then experienced varied degrees of fractional crystallization. According to the latest geophysical, sedimentological, and geochemical data, previous authors identified a Cretaceous E-W-trend subduction zone in the northern margin of the South China Sea. Combined with the southern margin magmatisms (110-80 Ma) and magmatisms of ~120 Ma distributed east-west ward from the Philippines to the Vietnam, We preferred that the subduction of the E-W-trend Neo-Tethys plate was the main geodynamic mechanism which induced the Cretaceous large-scale magmatisms in the southern margin of South China Block. [ABSTRACT FROM AUTHOR]

Amifostine is a cytoprotective drug that was initially used to control and treat nuclear radiation injury and is currently used to provide organ protection in cancer patients receiving chemotherapy. Clinical studies have also found that amifostine has some efficacy in the treatment of cytopenia caused by conditions such as myelodysplastic syndrome and immune thrombocytopenia, both of which involve megakaryocyte maturation defects. We hypothesized that amifostine induced the differentiation of megakaryocytes and investigated this by exposing the human Dami megakaryocyte leukemia cell line to amifostine (1 mmol/L). After 12 days of amifostine exposure, optical microscopy showed that the proportion of Dami cells with diameters >20 μm had increased to 24.63%. Transmission electron microscopy identified the development of a platelet demarcation membrane system, while flow cytometry detected increased CD41a expression and decreased CD33 expression on the Dami cell surface. Ploidy analysis found that the number of polyploid cells with >4N DNA content increased to 27.96%. We did not detect any elevation in the mRNA or protein levels of megakaryocytic differentiation-associated transcription factors GATA-binding factor 1 ( GATA-1) and nuclear factor, erythroid 2 ( NF-E2), but nuclear import assay revealed an increased nuclear translocation of these proteins. These findings indicate that amifostine induced the differentiation of Dami cells into mature megakaryocytes via a mechanism involving increased nuclear translocation of the transcription factors, NF-E2 and GATA-1. [ABSTRACT FROM AUTHOR]

Abstract: A new ligand, pyridine-3,5-bis(benzimidazole-2-yl) (pbb), and four complexes containing pbb, namely [pbb(Hpbb)2]SO4 ·7H2O (1), [Zn(pbb)2(H2O)4](NO3)2 ·2C2H5OH·4H2O (2), [Cd(pbb)2(H2O)4](NO3)2 ·2C2H5OH·4H2O (3) and [Zn2(pbb)2(μ-OH)(μ-OAc)](OAc)2 ·7H2O (4) (HOAc=acetic acid), have been designed, synthesized and characterized. Complexes 1–4 show 3D supramolecular architectures that are connected through hydrogen bonds and aromatic π–π interactions. A self-assembled (H2O)12 cluster with a chair conformation (H2O)6 ring core is observed in 1, which exhibits an unusual association mode of water molecules. Compounds 2 and 3 present 3D supramolecular structures involving 1D open channels encapsulating ions, and crown-like rings are found in 4. In addition, the preliminary antibacterial activity of pbb and its complexes were investigated by two methods, which indicate a selective inhibition property for the tested strains. Strong emissions from the complexes were also changed by the coordination modes in the sold state. [Copyright &y& Elsevier]

Methylation of the ribose 2'-hydroxyl, the most widespread modification of ribosomal and splicesomal RNAs, is guided by the box C/D class of small nucleolar RNAs (snoRNAs). Box C/D small nucleolar ribonucleoproteins (snoRNPs) contain four core proteins: fibrillarin, Nop56, Nop58 and 15.5 kDa. We constructed U25 snoRNAs containing a single photo-activatable 4-thiouridine at each U position within the conserved box C/D and C'/D' motifs. Proteins assembled on the snoRNA after injection into Xenopus oocyte nuclei were identified by cross-linking, and reconstituted particles characterized by functional rescue and mutational analyses. Our data argue that box C/D snoRNPs are asymmetric, with the C' box contacting Nop56 and fibrillarin, the C box interacting with Nop58, and the D and D' boxes contacting fibrillarin. No cross-link to 15.5 kDa was detected; its binding is disrupted by 4-thiouridine substitution in position 1 of the C box. Repositioning the guide sequence of U25 upstream of box D instead of if revealed that both C/D motifs have the potential to function as guide centers, but, surprisingly, there was no alteration in protein cross-linking. [ABSTRACT FROM AUTHOR]

The article presents a case study of 85-year-old male patient with transformation acute myeloid leukemia (AML) from myelodysplastic syndromes (MDS) who were treated with amifostine and ultralow dose decitabine. The patient was given erythropoietin with progressive decline in haemoglobin along with the collection of venous blood from cubital vein of patient. Ultralow dose decitabine combined with autologous Cytokine-induced killer (CIK) cells may provide a safe regimen for AML in patients.